Method of recording/reproducing ATV signals divided into trick play data and normal play data

ABSTRACT

A digital video tape recording method for trick play includes the steps of dividing the data area of a video sector of respective tracks of the digital video tape into first, second and third regions, interspersely recording normal play data and trick play data in the first and third regions, and recording the normal play data in the second region, wherein the trick play data recorded in the first and third regions is frame data corresponding to the maximum odd-fold speed of a plurality of given odd-fold speeds, and the same trick play data is repeatedly recorded for a number of tracks equal to twice the number of the maximum odd-fold speed, thereby enabling satisfactory trick play at various odd-fold speeds and with various scanners.

BACKGROUND OF THE INVENTION

The present invention relates generally to a digital video taperecording/reproducing method, and more particularly, to a method forrecording/reproducing video data for trick play in a digital video taperecording/reproducing apparatus which records/reproduces an advancedtelevision signal.

Recently, a commercial-purpose digital video cassette recorder has beendeveloped, which can record/reproduce the advanced television (ATV)signal on/from digital video tape for a standard-definition VCR. The bitstream of a standard-definition VCR is 24.9 megabits per second, whereasthe bit stream of the ATV signal is 19.3 megabits per second. Thisleaves an area for recording 5.6 megabits per second on the video tape.There has been much investigation as to how best to record trick playdata on the remaining video sectors and an unused audio sector in orderto facilitate trick play reproduction of the ATV signal at variousspeeds, as well as to accomodate various types of scanners, and in orderto improve picture quality and solve noise problems. The presentinvention, which resulted from one such investigation, encompasses atechnique for recording trick play data in such a manner as to enablethe realization of a desirable digital video tape player for the home.

A fundamental problem in digital video cassette recorder developmentlies in the recording format for special reproduction modes (trick playoperation). The format must be structured such that tworequirements--better picture quality and cost reduction--are satisfied.

One solution to the above problems is to allocate the trick play datathroughout the entire scanning area, portions of which respectivelycorrespond to each of a given set of playing speeds. This method canprovide better picture quality for a reproduced image during trick playoperation, but presents a drawback in that the correspondingly allocatedarea must be scanned, so that a servo control operation must be carriedout with a high degree of precision, thereby increasing the cost andcomplexity of the VCR, and degrading the reliability thereof.

An alternative solution is to repetitively record the trick play datanormally recorded on a pair of tracks onto a number of tracks whichcorrespond to twice the maximum-fold playback speed. In accordance withthis method, scanning is performed in the repetitively recorded areaonly, so that the servo control need not be so precise, which somewhatreduces cost and complexity. However, the repetitive recording mayconsume a large recording area, and the duration for displaying eachstill image is longer during low-speed playback than it is duringhigh-speed playback. This lengthy interval between updated images tendsto make the viewer impatient, and picture quality suffers as well.

SUMMARY OF THE INVENTION

To solve the above problems, it is an object of the present invention toprovide a digital video tape recording/reproducing method for trick playoperation which is compatible with a variety of scanners (heads).

It is another object of the present invention to provide a digital videotape recording/reproducing method which enables various odd-fold speedsof trick play.

It is still another object of the present invention to provide a digitalvideo tape recording/reproducing method which improves the picturequality during low-speed trick play.

To accomplish the first and second objects, the present inventionprovides a digital video tape recording method for trick play in whichATV signals containing frame data supplied at predetermined intervalsand independently decodable are divided into normal play data and trickplay data are and recorded on digital video tape. This method includesthe steps of dividing the data area of a video sector of respectivetracks of the digital video tape into first, second and third regions,intersperseingly recording the normal play data and trick play data inthe first and third regions, and recording the normal play data in thesecond region, wherein the trick play data recorded in the first andthird regions is frame data corresponding to a maximum odd-fold speed ofa plurality of odd-fold speeds, and the same trick play data isrepeatedly recorded for a number of tracks equal to twice the number ofthe maximum odd-fold speed.

To accomplish the third object of the present invention, there isprovided a digital video tape recording method for trick play in whichATV signals containing frame data supplied at predetermined intervalsand independently decodable are divided into normal play data and trickplay data are and recorded on the digital video tape. This methodincludes the steps of repeatedly recording DC coefficients and first ACcoefficients of respective DCT blocks of frame data corresponding to themaximum odd-fold speed of the frame data at predetermined locations ofrespective video sectors of a number of tracks equal to twice the numberof the maximum odd-fold speed, the DC coefficients and first ACcoefficients being supplied as trick play data for all odd fold speeds;repeatedly recording second AC coefficients of respective DCT blocks ofthe selected frame data on a first region of respective audio sectors oftracks equal to twice the number of a second odd low speed, the secondAC coefficients being supplied as part of trick play data for first andsecond odd low speeds; and repeatedly recording third AC coefficients ofrespective DCT blocks of the selected frame data on a second region ofrespective audio sectors of tracks equal to twice the number of a firstodd low speed, the third AC coefficients being supplied as part of trickplay data for the first odd low speed.

In another of its aspects, the present invention encompasses a digitalvideo tape reproducing method which includes the steps of dividing datareproduced from a tape into normal play sync blocks, all odd-fold speedtrick play sync blocks, second odd low-speed trick play sync blocks, andfirst odd low-speed trick play sync blocks; at odd high speeds, firsterror-correcting the divided trick play sync blocks for all odd-foldspeeds by using error correction sync blocks thereof, and outputtinghigh-speed trick play reproduced data; at odd low speeds, firsterror-correcting the divided trick play sync blocks for all odd-foldspeeds by using error correction sync blocks thereof, outputtinghigh-speed trick play data sync blocks, second error-correcting trickplay sync blocks for the second odd-fold speed by using error correctionsync blocks thereof, outputting the second odd low-speed trick play datasync blocks, and summing the high-speed trick play data sync blocks andsecond odd low-speed trick play data sync blocks, thereby outputting thesecond odd low-speed trick play sync blocks; and, at first odd lowspeeds, first error-correcting the divided trick play sync blocks forall odd-fold speeds by using error correction sync blocks thereof,outputting high-speed trick play data sync blocks, summing trick playdata sync blocks for the second odd-fold speed and trick play data syncblocks for the first odd-fold speed, third error-correcting the summedsync blocks by using error correction sync blocks, outputting theerror-corrected first and second odd low-speed trick play data syncblocks, and summing these data sync blocks and the high-speed trick playdata sync blocks, thereby outputting the first odd low-speed trick playsync blocks.

BRIEF DESCRIPTION OF THE DRAWINGS

The above objects and other advantages of the present invention willbecome more apparent with reference to the following detaileddescription of a preferred embodiment thereof, and with reference to theattached drawings, in which:

FIG. 1 depicts a track construction of digital video tape;

FIG. 2 depicts the structure of various scanners for scanning digitalvideo tape;

FIG. 3 is a diagram showing the division of the coefficients of each DCTblock of trick play frame data according to the present invention;

FIG. 4 depicts a record format of the video recording area for trickplay on the digital video tape according to the present invention;

FIG. 5 illustrates trick play data repetitively allocated on a pluralityof tracks of the digital video tape according to the present invention;

FIG. 6 depicts a record format of the audio recording area for trickplay on the digital video tape according to the present invention;

FIG. 7 illustrates trick play data repetitively recorded according tothe present invention;

FIG. 8 illustrates a scanning pattern of digital video tape in the caseof low-speed playback;

FIG. 9 illustrates a scanning pattern of digital video tape in the caseof high-speed playback;

FIG. 10 is a block diagram showing the digital video tape recordingapparatus according to the present invention; and,

FIG. 11 is a block diagram showing a digital video tape reproducingapparatus according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 depicts the track configuration of a digital video tape for thestandard-definition VCR. ATV signals are recorded in the recording areasof the track. Video-audio data of the ATV signals for normal play arerecorded on video sectors. As previously described, an unrecorded areais left on the video tape, since the bit stream for standard-definitionVCRs is 24.9 Mbps and that for the ATV signal is 19.3 Mbps.

Referring to FIG. 1, an ITI (Insert and Track Information) sector 2, anaudio sector 4, a video sector 6 and a subcode sector 8 appear along atrack in sequence, from the beginning portion of the track. A gap existsbetween the respective sectors. ITI sector 2 includes a preamble area, astart sync block area, a track information area and a postamble area.Audio sector 4 and video sector 6 will be described hereinafter. Subcodesector 8 includes a preamble area, a subcode area, and a postamble area.The area beyond subcode sector 8 is an overwrite margin.

FIG. 2 shows a variety of head structures of scanners for reproducing astandard-definition ATV signal from a digital video tape and thecorresponding track scan traces. More particularly, a two head scanner,a one double-azimuth head scanner and a two double-azimuth head scannerare shown. A different format for the recording of trick play data isrequired for each of these various heads.

The transport bit stream of an ATV signal is repeated, for instance, inthe sequence of I-P-B-B-P-B-B-P-B-B, where reference character Irepresents intra-frame data which can be coded independently, referencecharacter P represents predicted frame data which can be coded from thepreceding intra-frame data or predicted frame data using movementcompensation, and reference character B represents bidirectionalpredicted frame data which can be coded from the preceding intra-framedata or predicted frame data, and from the succeeding intra-frame dataor predicted frame data using movement compensation. Therefore, theintra-frame data, which can be coded independently, is selected from thenormal data so as to be used as the trick play data.

Referring to FIG. 3, in a preferred embodiment of the present invention,intra-frame data corresponding to 19-fold speed is selected. The ACcoefficient area of each discrete cosine transform (DCT) block of theselected intra-frame data is divided into multiple areas; for instance,into DC coefficient 31, first AC coefficients 32 (1, 2 and 4), i.e., thefirst data, second AC coefficients 33 (3, 5, 7, 8 and 12), i.e., thesecond data, and third AC coefficients 34 (6, 9, 11, 13, 17, 18 and 24),i.e., the third data.

The first data are used at 3, 7, 11, 15, 19, -5, -9, -13, and -17-foldspeeds in common. The second data are used at 3 and 7-fold speeds incommon. The third data are used only at 3-fold speed. At the 3-foldspeed, since the first, second and that for third data are all used foreach DCT block data, more AC coefficients can be used than at the highspeeds (which use only the first data) so that the high-frequencycomponent of an image is improved, which enhances picture quality. Atthe 7-fold speed, since the first and second data are used, picturequality is held intermediate between that for the high speeds and the3-fold speed.

FIG. 4 shows a preferred embodiment of the structure of video sectors ofeach track of the digital video tape according to the present invention.Video sector 6 has 149 sync blocks. That is, the video sector includes afirst video auxiliary data region 61 (sync blocks 19-20), a first trickplay data region 62 (sync blocks 21-60), a normal play data region 63(sync blocks 61-109), a second trick play data region 64 (sync blocks110-155), a second video auxiliary data region 65 (sync blocks 156-157),and an error correction outer parity region 66 (sync blocks 158-167).Each sync block includes a two-byte sync code 67, a three-byteidentification code 68, 77-byte data 69, and an eight-byte errorcorrection inner parity code 70. First and second normal/trick play dataregions 62 and 64 together constitute a region in which the pick up oftrick play data is made possible at all odd-fold speeds by tracing allthe scan tracks of given odd-fold speeds, e.g., 3, -5, 7, -9, 11, -13,15, -17-fold speeds.

The data recorded on first and second normal/trick play data regions 62and 64 are recorded as a mixture of normal play data and trick playdata, as shown in FIG. 5. More particularly, the trick play data arerecorded by selecting from the intra-frame data the frame datacorresponding to the maximum-fold speed, forming a plurality of syncblocks with the DC coefficients and first AC coefficient of each DCTblock, and allocating 30 sync blocks for every track. The 30 sync blocksare made up of 26 data sync blocks and four error correction code datasync blocks and are divided into sequential sync blocks a, b, c, d, e,f, g, h and i. For a track having a given azimuth, e.g., a positiveazimuth, the sequential sync blocks a, b, c, d, e, f, g, h and i arerecorded on first and second normal/trick play data regions 62 and 64,wherein the sync blocks are interspersely recorded at intervals of aboutfive to seven sync blocks of normal play data, from the beginningportion of the track, in the sequence of the sync block numbers. Also,part of the sequential sync blocks a, b, c and d is intersperselyrecorded on a track having the opposite azimuth (i.e., a negativeazimuth) in first normal/trick play data region 62, at intervals ofabout five to seven sync blocks of normal play data, from the centralportion to the beginning portion of the track, in the sequence of thesync block numbers. In second normal/trick play data region 64, theremaining sequential sync blocks e, f, g, h and i are intersperselyrecorded at intervals of about five to seven sync blocks of the normalplay data, from the end portion to the central portion of the track, inthe sequence of the sync block numbers.

The number of the sequential sync blocks is four or five at the centerof the normal/trick play data regions and two outwardly therefrombecause the center region is where the envelope of a signal picked-up bythe head is wide, with the signal envelope becoming narrower in the moreoutward regions, at odd-fold speeds such as 3, 7, 11, 15, 19, -5, -9,-13, and -17. If the speeds are even-fold, a portion in which the headscanning area overlaps becomes the center of the normal play data regionof the video sectors.

For sequential sync blocks a, b, c, d, e, f, g, h and i, five or sixsync blocks neighbor one another in the central portion of first andsecond normal/trick play data regions 62 and 64, and the number ofadjacent sync blocks decreases outwardly therefrom, the only constraintbeing that at least two adjacent sync blocks be present. In sum, theselected frame data include thirty sync blocks and the series syncblocks a, b, c, d, e, f, g, h, and i are divided into nine groups:(1,2), (3,4,5,6,7,8), (9,10,11,12), (13,14), (15,16), (17,18,19),(20,21,22,23), (24,25,26,27,28) and (29,30). Also, sequential syncblocks a, b, c, d, e, f, g, h and i, which are to be recorded on a pairof tracks having different azimuths, are recorded to lie at alternatingpositions with respect to each other. When data is to be picked up usingsuch an arrangement of the trick play data, the interval between thepositive-azimuth head and negative-azimuth head of the scanner isconsidered. Preferably, the interval comprises about six sync blocks, toensure that data not picked up by positive-azimuth head is picked up bythe negative-azimuth head.

With the present invention, since audio sector 4 is not used inrecording ATV signals onto digital video tape formatted for astandard-definition VCR, trick play data for flow speed is recorded onthe unused audio sector 4.

Referring to FIG. 6, audio sector 4 according to the present inventionincludes a second low-speed (7-fold) trick play data region 41 (syncblocks 2-5), a first outer parity code region 42 (sync blocks 2-5), afirst outer parity code region 42 (sync blocks 6-7) for error correctingthe second low-speed trick play data, a first low-speed (3-fold) trickplay data region 43 (sync blocks 8-10), and a second outer parity coderegion 44 (sync blocks 11-15) for error correcting the first low-speedtrick play data. Therefore, the DC coefficients and first AC coefficientof respective DCT blocks are recorded on the video sector for the trickplay data for 3-fold speed, and the second AC coefficients of therespective DCT blocks are recorded in the second low-speed trick playdata region 41 of the audio sector. The third AC coefficients of therespective DCT blocks are recorded in the first low-speed trick playdata region 43.

In other words, as shown in FIG. 7, the present invention provides adigital video tape recording method wherein an advanced television (ATV)signal is supplied at predetermined intervals and includes independentlydecodable frame data. This ATV signal is divided into normal play dataand trick play data and recorded on a digital video tape. In thisrecording method, for the first data 31 and 32 of the respective DCTblocks of the intra-frame data selected from the entire intra-frame datain response to the maximum-fold speed, i.e., 19×, to be supplied as thetrick play data for all-fold speeds (e.g., 3, 7, 11, 15, 19, -5, -9, -13and -17-fold speeds), the selected portion of the intra-frame data isrepetitively recorded at predetermined locations (i.e., the positionsshown in FIG. 4) of each video sector of 38 tracks, i.e., 38=2×19 (themaximum speed number). For the second data 33 of the respective DCTblocks of the intra-frame data selected in response to the 19-foldspeed, to be supplied as part of the trick play data for the first andsecond low speeds, i.e., the 3- and 7-fold speed trick play data, theframe data is repetitively recorded on the 2-fold speed trick play dataregion 41 of each audio sector of fourteen tracks, i.e., twice thesecond low speed number. Also, for the third data 34 of the respectiveDCT blocks of the intra-frame data selected in response to the 19-foldspeed, to be supplied as part of the trick play data for 3-fold speed,the frame data is repetitively recorded on first speed trick play dataregion 43 of each audio sector of six tracks (i.e., twice the 3-foldspeed number). That is, the second and third data of the respectiveblocks of the selected intra-frame data is recorded in the audio sectoron a pair of tracks having opposite azimuths, with half of the framedata being recorded on each track. Therefore, the data recorded on thepositive-azimuth track is different from that recorded on thenegative-azimuth track.

In the case of 3-fold speed, as shown in FIG. 8, 3-fold speed trick playdata 3A and 7-foldspeed trick play data (3, 7A) both recorded on theaudio sectors and all-fold speed trick play data (a, b, h, i) recordedon the video sectors are picked up, and 3-fold speed trick play data 3Band 7-fold speed trick play data (3 and 7B) and all-fold speed trickplay data (d, c, g, f, e) recorded on the video sectors are picked up bythe negative-azimuth head. As a result, all-fold speed trick play data(a, b, c, d, e, f, g, h, i), 3- and 7-fold speed data (3, 7A) and (3,7B), and 3-fold speed data (3A, 3B) are obtained, so that the highfrequency characteristic is improved, and thus, a sharper picture can beachieved. Therefore, when the 19-fold speed trick play data is picked upand reproduced at 3-fold speed, the picture quality is such that, eventhough it takes a long time to update the image, the effect of thedisplayed picture is still pleasing to the eye.

In the same manner as for the 7-fold speed data, the 7-fold speed trickplay data (c, d, e, f, g, b, a, i, h) are picked up to reproduce apicture. Therefore, although trick play data (3A, 3B) are not used ascompared with the 3-fold speed, the pictures are held at an intermediatequality at the 7-fold speed.

At 11-, 15- and 19-fold speeds, similar to the conventional method andas shown in FIG. 9, the trick play data recorded on the video sectorsare used to form a trick play picture. In other words, trick play data(a, b, e, h, i), and (d, c, a, g, f) are picked up at 11-fold speed,trick play data (a, c, d, f, g, i) and (b, i, h, f, e) are picked up at15-fold speed, and trick play data (b, d, e, f, h) and (d, c, a, i, g,e) are picked up at 19-fold speed. At the above 11-, 15- and 19-foldspeeds, since only the trick play data recorded on the video sectors arepicked up to reproduce a picture, the picture quality is decreased butrapidly refreshed as compared with the 3- and 7-fold speeds. Therefore,in spite of the somewhat degraded picture quality, the viewed effect issatisfactory.

As shown in FIGS. 8 and 9, since, as the speed increases to higher oddspeeds, the distance between the track of the positive-azimuth head andthe track of the negative-azimuth head becomes greater, the sync blocksbetween the positive- and negative-azimuth tracks of the trick play datarecorded on the video sectors are alternately disposed with respect toeach other. In the same azimuth track, the data are disposed atintervals of five to seven sync blocks. This configuration enablesplayback by several different scanners and at various odd-fold speeds.

In another of its aspects, the present invention encompasses a method ofreproducing the trick play data from the recording tape, wherein thedata reproduced from the tape is divided into normal play sync blocks,all odd-fold speed trick play sync blocks, second odd low speed trickplay sync blocks, and first odd low speed trick play sync blocks.

At odd high speeds, error correction sync blocks of all of the separatedodd-fold speed trick play sync blocks are used for first errorcorrection thereof and the error-corrected sync blocks are output ashigh-speed trick play reproduced data.

At the second odd low speed, the error correction sync blocks of all ofthe separated odd-fold speed trick play sync blocks are used for thefirst error correction thereof, and the high speed trick play data syncblocks are output. The error correction sync blocks of the secondodd-fold speed trick play sync blocks are used for second errorcorrection thereof, and the second odd low speed trick play data syncblocks are output. The high speed trick play data sync blocks and secondodd low speed trick play data sync blocks are summed, to thereby outputthe second odd low speed trick play sync blocks.

At the first odd low speed, the error correction sync blocks of all ofthe separated odd-fold speed trick play sync blocks are used for thefirst error correction thereof, and the high speed trick play data syncblocks are output. The second odd-fold speed trick play sync blocks andthe first odd-fold speed trick play sync blocks are summed and thenthird error-corrected using error-correction sync blocks. Theerror-corrected first and second odd low speed trick play date syncblocks are output, to be added to high speed trick play data sync blocksand output as the first odd low speed trick play sync blocks.

FIG. 10 is a block diagram of a digital video tape recorder constructedin accordance with a preferred embodiment of the present invention. Atransport stream is input to a transport stream decoder 102 and decodedtherein. The transmission header data and information data are separatedby transport stream decoder 102. The information data is input to MPEGheader decoder 104 which then decodes the data and further separatestherefrom the MPEG header data and information data. The transmissionheader data and MPEG header data are sent to and recorded in anoverheader information storage means 106. The information data which isseparated from the MPEG header data is sent to and decoded by a partialvariable-length decoder (VLD) 108, which then outputs trick play datafor multiple speeds, the second low-speed trick play data, and firstlow-speed trick play data. All three of these trick play data outputsare applied to overheader adder 110 and reformed along with theoverheaders supplied to overheader information storage 106. An errorcorrection code is added to the reformed information in error correctioncoder 112. The reformed information with error correction code isapplied to sync block arranger 114 and recorded with the normal playdata on the tape according to the above-described recording format.

FIG. 11 is a block diagram illustrating a digital video tape reproducingapparatus constructed in accordance with a preferred embodiment of thepresent invention. Data reproduced from the tape is output by separatingnormal play sync blocks therefrom via normal play sync block separater116. Meanwhile, the reproduced data is applied to trick play sync blockrecovery circuit 118 and output as all-fold speed trick play data,second low-speed trick play data, and first low-speed trick play data.All-fold speed trick play data is applied to first error correctiondecoder 122 to be error-corrected. The second low-speed trick play datais applied to the second error correction decoder 124 to beerror-corrected. The second low-speed trick play data and firstlow-speed trick play data are summed in adder 120, and applied to thethird error correction decoder 126 to be error-corrected. The firsterror-corrected data and third error-corrected data are summed in adder128, and the first error-corrected data and second error-corrected dataare summed in adder 130. The first error-corrected data, first summeddata and second summed data are respectively applied to dummytransmission data shuffler 132 and shuffled therein. The output ofshuffler 132 is output via normal/trick play selection switch 134.Alternatively, the first and second low-speed trick play data may besummed after respective error correction operations, instead of prior tothird error correction decoder 126.

As described above, with the method of recording trick play data of thepresent invention, if the frame data corresponding to the maximum-foldspeed is used without change at low speeds, even though the picturerefresh rate is low and the same picture is displayed for a long time,picture quality is relatively improved and viewers are not disturbed, ascompared with the high speeds.

In the above-explained embodiment of the present invention, the trickplay data for the first odd low speed and second odd low speed areadditionally recorded and reproduced on/from the audio tracks. However,the present invention is not limited to this particular embodiment. Thepresent invention provides a digital video tape recording method whereinan advanced television signal, being supplied at predetermined intervalsand including independently decodable frame data, is divided into normalplay data and trick play data to be recorded on digital video tape.Concerning the recording method, for the DC coefficients and first ACcoefficients of the respective DCT blocks of the frame data selectedamong the entire intra-frame data in response to the maximum odd-foldspeed, to be supplied as trick play data for all-fold speeds, a portionof the frame data is repetitively recorded on predetermined spots ofeach video sector having a number of tracks equal to twice the maximumodd-fold speed number. For the second AC coefficients of the respectiveDCT blocks of the selected frame data to be supplied as part of thetrick play data for the first odd low speeds, a portion of the framedata can be repetitively recorded on the respective audio sectors havinga number of tracks equal to twice the number of the first odd lowspeeds. In the reproducing method of the present invention, thereproduced data is divided into normal play sync blocks, all-fold speedtrick play sync blocks, and first odd low-speed trick play sync blocks.At odd high speeds, error correction sync blocks of the separatedall-fold speed trick play sync blocks are used for first errorcorrection and output as high-speed trick play reproduced data. At thefirst odd low speed, the error correction sync blocks of the separatedall-fold speed trick play sync blocks are used for first errorcorrection, and the high-speed trick play data sync blocks are output.The error correction sync blocks of the first odd-fold speed trick playsync blocks are used for second error correction, and the first oddlow-speed trick play data sync blocks are output. The high-speed trickplay data sync blocks and second odd low-speed trick play data syncblocks may be summed so as to output the first odd low-speed trick playsync blocks. Further, the present invention also provides for therecording of trick play data for a third odd low speed and higher, inthe same manner as that for the first and second odd low speeds.

Although several aspects and embodiments of the present invention havebeen described in detail hereinabove, it should be clearly understoodthat many variations and/or modifications of the basic inventiveconcepts herein taught which may appear to those skilled in thepertinent art will fall within the spirit and scope of the presentinvention as defined in the appended claims.

What is claimed is:
 1. A digital video tape recording method for trickplay in which advanced television signals containing frame data suppliedat predetermined intervals and independently decodable are divided intonormal play data and trick play data and are recorded on a digital videotape, said method comprising the steps of:dividing a data area of avideo sector of respective tracks of said digital video tape into first,second and third regions; and interspersely recording a first portion ofsaid normal play data and said trick play data in said first region andsaid third region, and recording a second portion of said normal playdata in said second region, said trick play data recorded in said firstregion and in said third region being frame data corresponding to amaximum odd-fold speed of a plurality of given odd-fold speeds; andrepeatedly recording said trick play data for a number of tracks equalto twice a number of said maximum odd-fold speed.
 2. A digital videotape recording method according to claim 1, wherein:said trick play datarecorded in said first region and said third region is recorded in unitsof a plurality of sequential sync blocks, and a number of said pluralityof sequential sync blocks is maximum at a center of said first regionand said third region and decreases outwardly therefrom.
 3. A digitalvideo tape recording method according to claim 1, wherein:said maximumodd-fold speed is 19-fold speed.
 4. A digital video tape recordingmethod according to claim 1, wherein:said given odd-fold speeds are 3,7, 11, 15, and 19-fold speeds in a forward direction and 5, 9, 13, and17-fold speeds in a reverse direction.
 5. A digital video tape recordingmethod according to claim 1, further comprising a step of:alternatelydisposing a plurality of sequential sync blocks recorded on a pair oftracks having different azimuths with respect to each other.
 6. Adigital video tape recording method for trick play in which advancedtelevision signals containing frame data supplied at predeterminedintervals and independently decodable are divided into normal play dataand trick play data and are recorded on a digital video tape, saidmethod comprising the steps of:repeatedly recording DC coefficients andfirst AC coefficients of respective DCT blocks of frame datacorresponding to a maximum odd-fold speed of said frame data atpredetermined positions of respective video sectors of a number oftracks equal to twice a number of said maximum odd-fold speed, said DCcoefficients and said first AC coefficients being supplied as said trickplay data for all odd-fold speeds; repeatedly recording second ACcoefficients of respective DCT blocks of said frame data on a firstregion of respective audio sectors of tracks equal to twice a number ofa first odd low speed, said second AC coefficients being supplied aspart of said trick play data for said first odd low speed and a secondodd low speed; and repeatedly recording third AC coefficients ofrespective DCT blocks of said frame data on a second region ofrespective audio sectors of tracks equal to twice a number of saidsecond odd low speed, said third AC coefficients being supplied as partof said trick play data for said second odd low speed.
 7. A digitalvideo tape recording method according to claim 6, said method furthercomprising the steps of:selecting frame data corresponding to saidmaximum odd-fold speed of said frame data and dividing said selectedframe data into a plurality of sequential sync blocks; recording saidplurality of sequential sync blocks onto video sectors of a pair oftracks having opposite azimuths, said plurality of sequential syncblocks being interspersely recorded on remaining portions of a videosector which is divided into three parts, excluding an intermediatepart, on a first track having a first azimuth, from a starting point ofsaid first track, in a sequence of sync blocks of said normal play data;and interspersely recording part of said plurality of sequential syncblocks on a first portion of said video sector which is divided intothree parts, excluding an intermediate part, on a second track having asecond azimuth opposite that of said first azimuth, from an intermediateportion to a starting point of said second track, in a sequence of syncblocks of said normal play data, remaining ones of said plurality ofsequential sync blocks being interspersely recorded on a second portionof said video sector, from an end of said track to an intermediateportion thereof, in said sequence of sync blocks of said normal playdata.
 8. A digital video tape recording method according to claim 6,wherein:said recording of trick play data recorded on said first regionof said audio sector is performed such that said second AC coefficientsof respective DCT blocks of said selected frame data are divided intotwo parts, said two parts being respectively recorded onto tracks havingopposite azimuths.
 9. A digital video tape recording method according toclaim 6, wherein:said recording of said trick play data recorded on saidsecond region of said audio sector is performed such that said third ACcoefficients of respective DCT blocks of said selected frame data aredivided into two parts, said two parts being respectively recorded ontotracks having opposite azimuths.
 10. A digital video tape recordingmethod according to claim 6, wherein:said first region of said audiosector lies nearer a starting portion of said track than does saidsecond region.
 11. A digital video tape recording method according toclaim 6, further comprising a step of:recording on said first region anerror correction outer code for facilitating error-correction of saidtrick play data recorded on said first region.
 12. A digital video taperecording method according to claim 6, further comprising a stepof:recording on said second region an error correction outer code forfacilitating error-correction of said trick play data recorded on saidsecond region.
 13. A digital video tape recording method according toclaim 6, wherein:said odd-fold speeds are 3, 7, 11, 15, 19, -5, -9, -13,and -17-fold; said second odd low speed is 3-fold; and said first oddlow speed is 7-fold.
 14. A digital video tape recording method for trickplay in which an advanced television signal containing frame datasupplied at predetermined intervals and independently decodable isdivided into normal play data and trick play data and recorded ondigital video tape, said method comprising the steps of:repeatedlyrecording DC coefficients and first AC coefficients of respective DCTblocks of frame data selected with respect to a maximum odd-fold speedof said frame data onto predetermined positions of respective videosectors of a number of tracks equal to twice a number of said maximumodd-fold speed, said DC coefficients and said first AC coefficientsbeing supplied as said trick play data for all odd-fold speeds;repeatedly recording second AC coefficients of respective DCT blocks ofsaid selected frame data onto respective audio sectors having a numberof tracks equal to twice a first odd low speed number, said second ACcoefficients being supplied as part of said trick play data for a secondodd low speed; and repeatedly recording third AC coefficients ofrespective DCT blocks of said selected frame data onto respective audiosectors having a number of tracks equal to twice said second odd lowspeed, said third AC coefficients being supplied as part of said trickplay data for said second odd low speed.